gstreamer problem

recordingbin = gst.element_factory_make("bin")src = gst.element_factory_make("alsasrc")src.set_property("device", device)	#recordingbin = gst.parse_launch("bin.( alsasrc device=%s %s )"%(device, output))capsfilter = gst.element_factory_make("capsfilter", "recordingcaps")caps = gst.caps_from_string("audio/x-raw-int,rate=8000,channels=2,width=16,depth=16,signed=(boolean)true")capsfilter.set_property("caps", caps)recordingbin.add(src)recordingbin.add(capsfilter)src.link(capsfilter)